多重血条的制作

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

public class TestHp : MonoBehaviour
{
 
        //背景色图片和前景色图片
        public Image background;
        public Image foreground;

        //血条信息
        public Text CurrentHPInfo;
        public Text CurrentHPLayer;

        //血条颜色信息数组 默认红黄绿蓝白
        public Color[] hpColors = { Color.red, Color.yellow, Color.green, Color.blue, Color.white };

        //一层血条的血量 默认100
        public int singleLayerHP = 100;

        //总血量 默认700
        public int totalHP = 700;

        //当前剩余血量
        private int currentHP;
        public int CurrentHP
        {
            get
            {
                return currentHP;
            }

            set
            {
                currentHP = value;
                CurrentHPInfo.text = CurrentHP.ToString();
                ShowHPLayer();
            }
        }

        private void Start()
        {
            CurrentHP = totalHP;
        }

        /// <summary>
        /// 改变血量
        /// </summary>
        public void ChangeHP(int num)
        {
            CurrentHP += num;
            if (CurrentHP <= 0)
            {
                CurrentHP = 0;
            }
        }

        /// <summary>
        /// 根据当前血量 来显示多层血条
        /// </summary>
        /// <param name="currentHP"></param>
        private void ShowHPLayer()
        {
            //0血的特殊情况
            if (CurrentHP == 0)
            {
                foreground.fillAmount = 0;
                CurrentHPLayer.text = "0";
                return;
            }

            //首先计算出当前血量是第几层血
            int layerNum = CurrentHP / singleLayerHP;
            //无法整除的情况下多加1层（例如550血需要显示第6层）
            if (CurrentHP % singleLayerHP != 0)
            {
                layerNum++;
            }
            CurrentHPLayer.text = layerNum.ToString();

            //根据层数获取对应前景色
            int foregroundColorIndex = (layerNum % hpColors.Length) - 1;
            //层数是颜色数组长度的整数倍时，颜色为最后1种颜色
            if (foregroundColorIndex == -1)
            {
                foregroundColorIndex = hpColors.Length - 1;
            }
            foreground.color = hpColors[foregroundColorIndex];

            //根据前景色获取对应背景色
            //只剩最后1层血时，背景色固定为黑色
            if (layerNum == 1)
            {
                background.color = Color.wh;
            }
            else
            {
                int backgroundColorIndex;
                if (foregroundColorIndex != 0)
                {
                    //前景色索引不为0就倒退1位（x不为0时，x层的背景色=x-1层的前景色）
                    backgroundColorIndex = foregroundColorIndex - 1;
                }
                else
                {
                    //否则为最后1位
                    backgroundColorIndex = hpColors.Length - 1;
                }

                background.color = hpColors[backgroundColorIndex];
            }

            //计算出要显示的血条长度
            float length = 1.0f * (CurrentHP % singleLayerHP) / singleLayerHP;
            //当前血量是一层血条代表血量的整数倍时，显示长度为100%
            if (length == 0)
            {
                length = 1;
            }
            //改变长度
            foreground.fillAmount = length;

        }

    public void OnClick()
    {
        ChangeHP(-30);
    }


}